1996 Ford Ranger 4.0 V6 have codes P0306 and P0174 need some advice please

I will rent the noids and check with plug 6 wire off at idle and above 2000 rpm to check it. Monday. Thanks

I checked the compression spec The lowest cylinder must be 75 percent of the highest. Cyl 6 is 86 percent of cyl 4, within spec. Thanks

Keep me posted i saw it was in spec that's why i didnt say anything.

I had a question on using the NOID lights. Should I test it cranking only and then running? To crank without starting I removed coil pack fuse No 19. Should I check it while cranking? And then while running?

Also does it make a difference when testing compression on a cold engine vs a hot engine? I would rather check it cold so I don't get burned.

Also I am uncertain how to secure spark plug boots on the plugs.I want to make it click once it engages the top of the plug securely but with these Bosch wires I can't get an affirmative click. What I do is pull gently back and forth to see if it's on the nub spot. Can you give me an idea how to get a good click when installing? I have strong hands but of the six wires I installed not one click.

Thanks

As far as the noid light goes you can check it for flashing while cranking or running the main thing is that there getting the injector pulse signal.The compression tests are down on a hot engine.As far as the spark plug wires not clicking into place i have seen some wires the wire end slide further up into the boot when trying to install the wire on the plug.Very frustrating i then get a different brand of wires.

Hi, did you mean to say the compression psi goes down with hot engines or are the compression checks supposed to be done on a hot engine?The spark plug wires clip inside do not seem to be slipping up. I will test the wires with a spare plug to check how they are supposed to click or not. Thanks

No i ment you do the compression test when the engine is warmed up.

I am writing this list to do so I remember:

1 Check cyl6 injector plug with noid.
2 Check engine running at idle and 2500 rpm removing plug wire to see if misses at 2500 rpm.
3 Change oil and filter once missing is fixed.
4 Please add to my list as I get test info to you.

I hope you had a pleasant holiday, mine was great. Thanks

I had a great holiday as well thanks for asking.What are the current codes now?

Last time I drove it 2-3 weeks ago codes were P0300 and sometimes P0174. I will do the noid and missing tests when it's not so cold here. Thanks

I kind of feel the noid test is unceccessary since I did it only 30 miles ago, back in June 2012. My hands get bruised and torn up. I will wear gloves from now on, either leather or nitrile. I can check whether it misses at 2500 rpm by removing the cyl 6 wire at the coil pack and see if rpm drops. Is there a better way to detect misses for sure at 2500rpm? Thanks, Pete

I forgot to ask you I sent a ten dollar donation to you through another question you answered for me, did you get it? From last week.

I found the following tip on detecting a misfire.

TECH TIP
The Paper Test
A soundly running engine should produce even and
steady exhaust at the tailpipe. You can test this with
the paper test. Hold a piece of paper or a 3 by 5
index card (even a dollar bill works) within 1 inch
(25 mm) of the tailpipe with the engine running at
idle.
The paper should blow out evenly without
“puffing.” If the paper is drawn toward the tailpipe
at times, the exhaust valves in one or more cylinders
could be burned. Other reasons why the paper might
be sucked toward the tailpipe include the following:
1. The engine could be misfiring because of a lean
condition that could occur normally when the
engine is cold.
2. Pulsing of the paper toward the tailpipe could
also be caused by a hole in the exhaust system.
If exhaust escapes through a hole in the exhaust
system, air could be drawn in during the intervals
between the exhaust puffs from the tailpipe to
the hole in the exhaust, causing the paper to be
drawn toward the tailpipe.
3. Ignition fault causing misfire.

I can prop the pedal at 2500 rpm and check it with the plug wire on and off.
Now I just have to go do it.

After reading some more in this book, I will ground the plug wire at the plug. I will use my little sparker device to allow the coil to create a normal spark while wire is dc. This is to prevent damage to the coil pack. Also I learned the way to check is for RPM drop. The miss firing cyl gives the least rpm drop when dc.

I am checking to see if I got that donation thank you for it.Also keep me posted on these tests your running.

Hi saturntech9, Do you think the coil pack might be at fault? The cyl6 wire was shorting out for a long time before I started getting P0306. If I am getting spark at the no6 coil pack with a spark checker is it good or can the coil pack be a weak spark? If it sparks at all is it a good coil pack? If there's a spark problem on cyl6 should I also be getting cyl2 P0302 codes? Thanks Did you get the donation from Early January?

My main question is whether a constant shorting of the no 6 spark will damage the coil? From the images on my previous reply you can see the no6 was shorting to the ex manifold for quite a while. Thanks

Yes I got the other donation thank you. To check to see if the spark is strong enough take a old spark plug and see if your getting a nice blue spark not yellow or white?Did you replace that split boot?Also I want tell you if the coil is failing when it gets hot.Can you feel a miss at idle or driving down the road?What are the current codes since your latest repair?

I can't drive it since it's not registered. There is a bad miss at idle as though the cyl6 is not firing at all.I replaced all wires. I will check when hot and with a spare plug or my spark checker tool. Looking for blue spark right? Last codes were P0306 and P0174. I will recheck codes after I run it for a while. Thanks, Pete

Looking for blue spark keep me posted.

I get steady blue spark attaching an old spark plug to no6 plug wire and ground. It was more blue at the center electrode than near the side post. When I turned the truck on it had code p0306. I cleared it and after running at 3300 rpm for a minute it flashed the mil and had code p0300.
Checking for puffs at the tail pipe, at idle had noticeable puff every few seconds or so.At 2200 rpm same deal but smaller puffs. At 3300rpm did not noticeably puff. After ran at 3300 rpm the mil started to blink and got code P0300. The truck was completely warmed up.

Do you think the cause could be a severe leaking of the intake manifold gasket? Especially near no6?

Is there a way to test specifically for a leaking Intake manifold gasket?

I have the parts to make a smoke machine from a fog machine that I talked to you about way back when.

Is there a way to show a leaking gasket besides a smoke machine?
If I knew what the intake vacuum was normally I could use a vacuum gauge to see if it dropped.
Thanks for your help.

The best way to check for a leaking intake manifold is with smoke.If the missing is happening at 3300 rpm its not the intake leaking causing it.You may have some dirty injectors if there is new plugs etc.

Hi, at 3300 rpm it didn't miss, no puffs at tailpipe. I may try to get permission slips to drive it unregistered. That way I can see what codes will pop up. Or will I be able to get all codes standing still? Is there a pattern I should run at?
The smoke machine is connected to the brake booster right?
The best way to check intake is smoke but are there other methods? I can never check by spraying carb cleaner around to see if engine changes. I just don't know what to look for the change is so subtle. I read I can spray carb cleaner while looking at the short term fuel trim, bank 02 is the no 6 cyl right? This is what I will do next. What do you think?

I just read through my previous posts. I think I will check for blue spark at coil too.

Sounds good keep me posted.

I was asking myself why is it taking so long to figure out this issue. Well at a shop they would be throwing new parts at it in rapid succession and would have already determined it's an intake gasket problem by smoking it. I am afraid to remove the intake because I may never get it back together. I have a 1995 Toyota Motorhome with the timing chain job half finished sitting for 4 years. I have all the parts safe but just can't get going on it. There's mechanic locally who wants me to pay before he comes to work on it. All I really need is to hire a helper for $10/hour to stand there while I finish it. This would force me. It's starting to get cold again here so I may not get back to the Ranger for a couple days. Thanks for your help, Pete

Your welcome keep me posted.

Hi again, today I relaced the coil pack but am still receiving codes P0300 and P0174 after driving for 5 miles and idling a little. My friend said it may be a leaking intake gasket near bank 2, Cyl 6. This is what I thought at the start of this thread. I will put my smoke machine together from a fog machine and fish air pump I have. Can I use a square soap bucket about 3-4 gallons instead of a round five gallon bucket to collect the smoke? You told me how to do it in our first posts. I just haven't built it yet. Thanks for any suggestions.

For the intake gasket leak, how can I make the computer stay in open loop, ie not auto adjust the mixture? I read to remove the TPS plug is this ok? I was thinking of using my PC scan tool to watch the short term on bank 2 while spraying carb cleaner. Is this the way?

You can watch short term fuel trim while spraying carb spray.But smoke is truly the best way to look for a vacuum leak it can find the smallest leaks.I built a smoke machine with a old paint pot sprayer glow plug fish pump that uses denatured mineral oil that I got a feed store.You could even use a card board box.

Hi could you post some pics of your setup? I heard there are self shutoff glow plugs that shut off at too high a temp. Is that what you have? I am most interested in how it screws/JBwelds together. Thanks

I snapped a pic of my smoke machine can you give me your email address and I will email you the pic.Yes I used a ac delco self limiting glow plug.I will also get you a part number for that also.I only used jb weld around the glow plug where it fits in the bottom of the paint sprayer.

Thanks my email is [email protected]. Your machine is 12 volt right? How does JB weld hold up so far with the heat? Thanks, Pete

Jb weld holds up just fine the glow plug part number is ac delco part number 60g its 12 volts. I will email you the pic.

Hi Thanks for the pic, the black hose goes to the intake right? Is the clear tube the pressured air coming from the fish pump? You can use baby oil right if you can't get mineral oil? How long till it smokes, 2 minutes, 5 minutes, 10 minutes? Have you ever been able to examine a $1000 Smoke Pro? I read I should put saran wrap over the air filter element when testing. Thanks for your help

Yes the black hose is to the intake and clear hose is the fish pump.It takes a couple of mins to start smoking. I would only use the denatured mineral oil they sell at feed stores. They use it on horses coats/skin.The smoke pro uses the same mineral oil but never seen one in person.But works similar to the one I made.